Alarm system for swimming pools and the like



@mmm awww H smaamfr' Dec- 2. 1969 H. F. HAMBURG ETAL 3,482,237

ALARM SYSTEM FOR SWIMMING FOOLS AND THE LIKE Filed Oct. 22, 1965 2 Sheets-Sheet l a 6i ad De 2, 1959 H. F. HAMBURG ETAL 3,482.237

ALARM SYSTEM FOR SWIMMING FOOLS AND THE LIKE Filed oct. 22. 1965 2 Sheets-Sheet 2 United States Patent O U.S. Cl. 340-261 3 Claims ABSTRACT F THE DISCLOSURE An alarm system for a swimming pool having a float for rising and falling with the Water level, an alarm adapted for actuation by a switch, and a motion-sensitive coupling between the float and the actuator of the alarm switch for transmitting motion of the lloat to the actuator only when the velocity of the float exceeds a preselected velocity.

The present invention relates to alarm systems and, more particularly, to a novel alarm system for swimming pools and the like.

Although swimming pools provide a source of pleasurable recreation for individuals and families alike, when unattended, they present a serious danger, particularly to small children. The alarming news reports of accidental child drownings attest to this fact.

In an attempt to reduce this needless loss of life, numerous systems have been devised to generate an alarm signal when an object or body, falls or jumps into an unattended swimming pool. Such systems operate either in response to sound waves developed in the water, or by waves produced at the surface of the water. In both cases however, some sort of threshold device is included in an attempt to insure that the alarm system will not be accidentally energized by wind, rain, falling leaves, small stones and the like, and that it will always be energized by objects at least the size of a small baby falling into the associated swimming pool.

Unfortunately, presently available swimming pool alarm systems, including such threshold devices, are generally relatively complex, both in structure and in operation, and are likewise quite expensive. Also, some type of special mounting arrangement is usually required for the alarm systems. For these, as well as other reasons, swimming pool alarm systems have found only limited use.

It is therefore an object of the present invention to provide a simplified, inexpensive alarm system for swimming pools which overcomes the disadvantages of presently available systems, While including all the necessary and desirable characteristics and features of swimming pool alarms.

Another object of the present invention is to provide an alarm system of the foregoing character which operates only in response to sudden changes in swimming pool water level adjacent the alarm (surface waves) of the type caused by a large object, at least the size of a baby, falling or jumping into the pool.

A further object of the present invention is to provide an alarm system of the foregoing character which is easy to install and which in one form is easily transportable from one location to another or removable for storage when not in use.

The foregoing as well as other objects and advantages of the present invention may be more clearly understood by reference to the following detailed description when taken with the drawings, which, by way of example only, illustrate two forms of alarm systems embodying the features of the present invention.

3,482,237 Patented Dec. 2, 1969 I'Ce In the drawings: FIGURE 1 is a sectional side view of a portable form of alarm system stationed on top of the deck of a swim-` ming pool;

FIGURE 2 is a sectional top View of the alarm system of FIGURE 1;

FIGURE 3 is a wiring diagram of the electrical circuitry for the alarm system of FIGURE 1;

FIGURE 4 is a wiring diagram of an alternate form of the circuitry for the alarm system of FIGURE l;

FIGURE 5 is a sectional side view of the water level sensing portion of a different form of alarm system including an alarm located at a station remote from the swimming pool, the water level sensing portion being stationed in the side wall of the swimimng pool; and

FIGURE 6 is a enlarged fragmentary sectional side view of a portion of the water level sensing portion illustrated in FIGURE 5.

In the drawings, the alarm system is represented generally by the numeral 10 and includes an alarm portion 12 and a water movement sensing portion 14 for actuating the alarm portion when objects or bodies above a certain predetermined mass fall, drop or jump into the water 16 of a swimming pool 18.

Generally speaking, the sensing portion 14 includes an alarm actuating switch 20 and a pair of movable members 22 and 24 connected by a motion-sensitive, uid coupling device 26 having a predetermined threshold of coupling operation. The movable member 22 is adapted to operate the alarm-actuating switch 2()` while the movable member 24 is adapted to sense and move in response to movement of the water 16 in the swimming pool 18.

If there is only gentle movement of the water 16, as during normal pool water circulation, or minor wave motion, as produced by wind, rain, falling leaves and the like, then the movable member 24 moves slowly with the pool Water. Such motion of the movable member 24 is below the threshold of coupling operation of the coupling device 26 and the movement of the movable member 24 is not coupled to the movable member 22, which remains stationary relative to the movable member 24. Under such conditions, there cannot be an actuation of the alarm portion 12 by the actuating switch 20.

However, if a large object or body, at least about the size and Weight of a small child or baby, falls or jumps into the swimming pool 18, waves are developed in the water 16 which produce rapid movement of the movable member 24, equal to or above the threshold of operation of the coupling device 26. When this occurs, the coupling device 26 connects the movable member 24 to the movable member 22, causing the movable member 22 to move with the movable member 24 to operate the switch 20 and actuate the alarm portion 12 of the system 10. This operation is simple, rapid, and dependable, and provides a true warning indication that an object at least the size of a baby has fallen or jumped into the unattended swimming pool 18 and, more than likely, needs immediate assistance.

Referring now more particularly to FIGURES 1 and 2, a portable form of the alarm system 10 is illustrated. As represented, the alarm system is supported by a transportable housing 28, here illustrated as comprising a rectangular box having a removable top 30, a flat bottom 32, and front, rear, left and right side walls 34, 36, 38 and 40 extending upwardly from the bottom. In the ilustrated form, a generally L-shaped partition 42 is connected, as by welding, to the front and left side walls 34 and 38 at a front left corner of the housing and forms an elongated, rectangular compartment 44 for supporting the water motion sensing portion 14 of the alarm system 10. A generally L-shaped partition 46 is connected to the front and right side walls 34 and 40 at the front right corner of the housing to define a compartment 48 for a time control unit 50 for the alarm portion 12 of the system 10. The remainder of the housing28 denes a compartment 52 for the alarm portion 12 which, in the illustrated form, includes a conventional bell alarm 54 including the bell S, a solenoid 56, and a clapper 57 actuated by the solenoid. The bell alarm 54 is supported by and rests upon the bottom 32 of the housing 28. The bottom 32 also supports a battery S8 and a manually operable, normally open, master control switch 60 for electrically connecting the battery 58 to the bell alarm 54 to energize the alarm upon operation of the actuating switch 20. a

In the illustrated form of the Water movement sensing portion 14, the actuating Switch 20 is a normally open switch supported within a case 62 and having a movable switch arm 64 extending from the case. The case 62 is connected to the partition 42 parallel to the left side wall 38 of the housing 28 by a pair of screws 66 with the switch arm 64 facing in a downward direction within the compartment 44.

The movable member 22 is also stationed within the compartment 44 and, in the illustrated form, comprises a at arm pivotally supported at one end by a pin 68 eX- tending between side arms 70 of a bifurcated hinge unit 72 on the bottom 32 of the housing 28. An opposite end of the movable member 22 rests on an adjustable set screw 74 extending upward through the bottom 32. Thus supported, the movable member 22 lies generally parallel to the bottom 32 directly below the movable switch arm 64 of the actuating switch 20 and is adapted for swinging movement in a -vertical plane above the set screw 74 to operate the actuating switch.

The movable member 24 of the sensing portion 14 includes generally horizontal inner and outer portions 76 and 78 and a generally vertical connecting portion 80 therebetween. One end of the horizontal portion 76 includes an enlarged, laterally extending tubular head 82 pivotally connected by a pivot pin 84 to the partition 46 above the hinge unit 72 for the movable member 22. The opposite end of the horizontal portion 76 is connected to the vertical portion 80 and extends through a vertical opening 86 in the front wall 34 of the housing 28 for movement in the vertical plane of the movable member 22.

The outer end 87 of the horizontal portion 78 is tubular and is adapted to slidably receive one end of an L-shaped arm 88. The L-shaped arm 88 is releasably secured within the tubular portion 87 by a thumb screw 90, while an opposite end of the arm is connected to the top of a oat 92. The float 92 is adapted to ride on top of the surface of the water 16 in the swimming pool 18 when the transportable housing 28 is located adjacent the edge of the pool on top of the pool deck. The location of the float 92 within the water 16 is adjustable by sliding the L- shaped arm 88 inward or outward within the tubular portion 87 and by the same token, the L-shaped arm and float are removable from the movable member 24 when it is desired to transport the alarm system or to place the system in storage.

The coupling device 26 between the movable members 22 and 24 may take various forms, each having the characteristic of a predetermined motion threshold of operation below which the movable member 24 moves freely, independent of the movable member 22 and at and above which movements of the movable member 24 are imparted to the movable member 22 causing the movable member 22 to operate the actuating switch 20 and energize the alarm portion 12 of the system 10.

In the illustrated form, the motion sensitive coupling device 26 comprises a dash pot including a piston 94 and a cylinder 98. The piston 94 is connected by a vertical rod 96 to the movable member 22l above the set screw 74 formed in the horizontal inner portion 76 of the movable member 24.

The upper end of the cylinder 98 includes a conventional bleed valve 102 for allowing the escape and entry of uid from and to the top of the cylinder as the piston 94 moves up and down within the cylinder. In addition, the inner walls of the cylinder 98 and the outsi-de of the piston 94 are shaped such that there is a certain amount of fluid passage around the piston as it mov-es up and down within the cylinder. A dash pot is commonly considered to be a velocity sensitive and responsive device. Therefore, by control of the fluid flow in and out of the cylinder 98 with movement of the piston 94, the velocity threshold of coupling operation for the dash pot comprising the device 26 may be preset or altered as desired.

In particular, because of the fluid coupling provided by the piston 94 and cylinder 98, as well as the passage of fluid from within and without the cylinder, when the movable member 24 moves slowly in response to movements of the water 16 in the swimming pool 18, fluid within the cylinder has sufficient time to leak out of the cylinder as the movable member 24 moves downward and to return 'when the movable member 24 moves upward. Under such conditions, the movable member 22 remains stationary as the movable member 24 moves up and down. Depending upon the opening provided by the bleed valve 102 and the design of the cylinder 98 and piston 94, at and above a particular velocity for the movable member 24 there is insuicient fluid leakage from the cylinder during its downward stroke and insufficient fluid entry into the cylinder during its upward stroke such that a vacuum is create-d within the cylinder during the upward travel of the movable member 24 which causes the piston to move with the cylinder in an upward direction. As this occurs, the movable member 22 moves with the piston to operate the switch 24 by depressing the movable switch arm 64. The value of the upward velocity of the movable member 24 at which the coupling device 26 produces a following movement of the movable member 22 is considered to be the velocity threshold for the coupling device. The greater the fluid leakage from and fluid entry into the cylinder 98, of course, the higher the threshold and the lower the seepage from and fluid entry into the cylinder, the lower the threshold.

Adjustment of the set screw 74 also provides a degree of control over the actuation of the alarm system 10 since the closer the movable member 22 to the switch 20, the shorter the movement of the member 22 required to actuate the switch and the alarm portion 12 of the system 10. Likewise, the further the movable member 22 from the switch 20, the greater the travel of the movable member 22 required to operate the switch. The position of the set screw 74 in controlling the distance between the movable arm 22 and the actuating switch 20, thus controls the minimum height of surface wave which will cause the movable arm 22 to operate the actuating switch and hence the alarm portion of the system 10.

Accordingly, in the alarm system 10, the uid coupling device 26 and set screw arrangement 74 require a predetermined minimum wave velocity for the water 16 within the pool 18 before there is any coupling between the movable members 24 and 22 and thereafter a minimum height surface wave before the switch 20 is actuated by the movable arm 22 to energize the alarm. These controls are preferably adjusted to correspond to the minimum splash and water movement created by a small baby jumping or falling into a swimming pool 18 from the edge thereof. Water movement within the pool 18 below the velocity threshold and surface waves below the minimum determined by the set screw arrangement 74 will not produce an actuation of the alarm system 10 thereby while the cylinder 98 has an open bottom for receiving 75 Preventing accidental energiZIlg 0f the alarm and insuring the piston 94 and a top portion stationed within a ring 100 that when the alarm is sounded, there is a true indication that an object or body at least the size of a small baby has fallen, dropped or jumped into the swimming pool.

In summary then, when an object or body of a predetermined minimum size and weight falls into the swimming pool 18, surface waves are developed in the pool causing the movable member 24 to move up and down at a velocity equal to or in excess of the predetermined velocity threshold of the coupling device 26. With movement of the movable member 24 at or in excess ofthe operating threshold of the coupling device 26, the coupling device transmits movements of the movable member 24 to the movable member 22 causing the movable member 22 to move upwardly with the movable member 24 downward movement of the movable member 22 being limited by the set screw 74.

The height of a surface wave generated by the falling body is suicient to cause the movable member 22 to engage the switch arm 64 of the actuating switch 20 with vertical movement of the movable member 24. Accordingly, vertical movement of the movable member 22 momentarily closes the normally open actuating switch 20, which again reopens with downward vertical movement of the movable member 22 away from the actuating switch.

As illustrated most clearly in FIGURE 3, which rep` resents a wiring diagram for the alarm system illustrated in FIGURES l and 2, the momentary closing of the actuating switch completes a series loop circuit including the battery 58, the previously closed master switch 60, and a solenoid 104 of the time control unit 50. Briey, in addition to the solenoid 104, the time control unit 50 -includes a time control switch unit 106 having a fast operate time and a slow release time. Current ow through the solenoid 104 energizes the control switch unit 106 to rapidly close and complete a current path from the battery 50 through the master control switch 60, the control switch unit 106 and the solenoid 56 for the bell alarm 54, back to the battery. Current iiow through the solenoid 56 actuates the clapper 57 to repeatedly and rapidly move against the bell 55 to sound an alarm.

Since the closing of the actuating switch 20 is only momentary, current flows through the solenoid 104 of the time control unit 50 only for a short period of time. However, due to the slow release of the control switch unit 106, current continues to iiow to the bell alarm solenoid 56 for a predetermined period of time. Thereafter, however, the control switch unit 106 opens to stop the alarm and a subsequent operation of the actuating switch 20 is required to repeat the operation.

The structural arrangement of one form of the time control unit 50 is most clearly illustrated in FIGURE 2, within the compartment 48 dedined by the partition 46. As represented, the solenoid 102 is supported on the bottom 32 of the housing 28 with a movable plunger 107 extending therefrom and movable in and out of the winding of the solenoid. The outer end of the plunger 107 engages one side of a switch actuating arm 108 hinged for swinging movement toward and away from the solenoid 102 by a vertical pin 110 connected at one end of the arm. A coil spring 112 is connected to an opposite end of the arm y108 and to a vertical pin 113 to continuously urge the arm toward the plunger 107. The opposite end of the switch acuating arm 108 is also connected to a rod 114 extending from a viscous damping unit 116. Viscous damping unit 116 produces the slow release time for the control switch unit 106 and in the illustrated form cornprises a piston 118 connected to the end of the rod 114 for movement within a cylinder 120 connected to the inside wall of the partition 46.

A normally open control switch 122 is stationed on a side of the switch actuating arm 108 opposite the plunger 107 with a movable switch arm 124 engaging the actuating arm. Thus positioned movement of the plunger 107 away from the winding of the solenoid 102 produces a counterclockwise swinging movement of the switch actuating arm 108 (when viewed from the top) to close the normally open control switch 122 and to drive the piStOn 118 into the cylinder 120. Upon termination of current flow through the solenoid 102, the switch actuating arm 108 remains in its counterclockwise position to close the control switch 122 despite the spring force exerted on the arm 108 by the spring 112. Slowly, however, the viscous damping unit 116 allows the switch actuating arm 108 to return to its normal position under the force of the spring 112 at which time the control switch 122 returns to its normally open condition, terminating current ow to the bell alarm 54.

An alternate form of the electrical circuitry for the alarm system 10 is illustrated in FIGURE 4. The circuit of FIGURE 4 does not include a time control unit. Rather the circuit includes a self-latching feature which maintains the bell alarm 54 in operation after the actuating switch 20 has opened and until the master control switch 60 is manually opened by a pool attendant. To accomplish this, the circuit of FIGURE 4 includes a relay 125 having a winding 126 and two pair of normally open contacts 128, and 132, 134. The winding 126 is connected in two diierent `series loop circuits. The first loop circuit includes the actuating switch 20, the master control switch 60 and the battery 58. The second loop circuit includes the pair of normally open contacts 128, 130 the master control `switch 60 and the battery 58. The pair of normally open contacts 132, 134 are connected in series with the master control switch 60, the bell alarm 54, and the batte-ry 58.

In the circuit of FIGURE 4, momentary closing of the actuating switch 20 completes a series circuit from the battery 58 through the winding 126 to close both pairs of normally open contacts. The closing of the pair of normally open contacts 132, 134, completes a current path from the battery 58 through the master control switch 60 to the bell alarm 54 to actuate the alarm. The closing of the pair of normally open contacts 128, 130, short circuits the actuating switch 20 to complete a series circuit directly from the battery 58 through the master control switch 60 and the winding 126. This maintains the relay 125 and hence the bell alarm 54 in an operating condition until such time as the master control switch 60 is manually opened.

An alternate form of the Water movement sensing por.- tion 14 for a built in version of the swimming pool alarm system 10 is illustrated in FIGURES 5 and 6. The alarm portion 12 for the system may be at a remote location and may include an audio or visual alarm or alternatively may include the electrical circuitry illustrated and described in connection with FIGURES 3 and 4.

The sensing portion 14 of the alarm system 10 is supported within a box 136, preferably formed of a corrosion resistant material, located in a generally rectangular recess 138 in the side wall 140 of the swimming pool 18. A portion of the coping block 142 above the recess 140 is removable to allow the 'box 136 to be slipped into the recess from the deck of the pool. The box 136 sits at the back of the recess 138 with a conduit 144 for the wiring to the alarm portion 12 extending from the back of the box.

The movable member 24 of the sensing portion 14 extends from the front 146 of the box 136 through the recess 138 and into the pool 18 where it connects to a iloat 148 for riding on top of the surface of the water 16 in the pool. The front of the recess 138 is partially covered by a tile plate 150 with a vertical opening 152 for receiving the movable member 24. A grill 154 supported by a ring 156 extends over and above and below the oat 148 to protect the float 148 while allowing for movement of the float in a vertical plane. The ring 156 is connected to the tile plate 150 through a bolt-nut cornbination 158.

Water from the pool 18 is permitted to ow through the opening 152 into the recess 138 outside the box 136.

To prevent stagnation of the water within the recess 138 and to insure complete water circulation, the side wall 140 of the pool 18 includes a outlet port 160 leading from the recess 138 to the side of the pool. The port 160 communicates with the water circulation system for the swimming pool and preferably the return 162 from the lter of the circulation system. The water flow from the circulation system into the outlet port 160 creates a suction in the port w-hich draws surface water from the pool 18 to the recess 136 down the port and back into the pool.

Within the box 136, the physical arrangement of the movable members 22 and 24, and coupling device 26 is very similar to that of the corresponding parts of the water movement sensing portion described in connection with FIGURES 1 and 2. In particular, the case of the actuating switch 2t) is connected to a side wall 164 of the box 136 with the movable switch arm 64 facing in a downward direction.

The movable member 22 comprises a at arm pivotally connected to a back 166 of the box with the front end pivotally connected to the vertical rod 96 of the coupling device 26. Thus supported, the movable member 22 is adapted to move up and down in a vertical plane in response to vertical movements of the rod 96.

As before, the rod 96 connects to the piston 94 within the cylinder 98. The cylinder 98, in turn, is pivotally connected at its upper end to a portion of the movable member 24 between its innermost end and a pivot support 168 for the movable member to the front wall 146 of the box 136.

The movable member 24 comprises an elongated rod while the pivot support 168 includes an annular socket 170 in the front wall 146 and a ball 172 integral with the rod and seated within the socket. Surrounding the movable member 24 immediately outside the box is a bellowstype seal 174 connected to the front wall 146, as by a plurality of screws. The outer end of the bellows seal 174 is sealed by a tubular plug 176 connected to the rod by a set screw 178. The bellows seal prevents pool water from sepping around t-he movable lmember 24 into the ball and socket connection.

In addition to the movable members 22 and 24, and the coupling device 26, the box 136 provides support for high and low water level indicating switches 180 and 182. The high and low water level indicating switches 180 and 182 are connected to the side wall 164 of the box 136 and lie in a substantially vertical plane below and above the horizontal plane of the ball and socket combination, respectively. The high and low water level indicating switches 180 and 182 each includes a movable switch arm 184 adapted to be contacted and actuated by a contact block 186 connected to the inner end portion of the movable member 22 by a set screw 188. An adjustable screw 190 extends through a pair of lateral arms 192 adjacent the low water level indicating switch 182 to act asy a stop member by engaging the movable member 22 in its low water level position.

t he high and low water level indicating switches 180 and 182 are spaced vertically on either side of the ball with external circuitry (not shown) to produce either ra visual or audible indication of the low or high water condition or alternatively automatically start or stop the water supply to the pool 18.

The balance of the Aoperation of the movable member 24 and the coupling device 26 to produce movement of the movable member 22 is as previously described in kcon- 8 nection with FIGURES l and 2. Thus, minor surface waves in the pool 18 will not produce a movement of the movable member 22. On the other hand, movement of themovable member 24 at a rate greater than or eqal to the threshold of the device 26 will cause the movable member 22 to move with the movable member 24 to operate the actuating switch 20 and thereby energize the alarm portion 12 of the system 10.

Accordingly, the present invention provides an improved alarm system for swimming pools and the like which is extremely simple in design yet which possesses a threshold of operation preventing accidental operation of an alarm and insuring that when the alarm is sounded an object at least the size of a small baby has fallen or jumped into the swimming pool.

We claim: y

1. An alarm system for swimming pools, comprising,

an alarm actuating switch;

a rst movable member for operating said switch;

a second movable member for moving in response to swimming pool water movement;

and motion sensitive coupling means between said rst and second movable members for connecting said rst movable member to move with said second movable member, operate said switch and actuate said alarm when motion of said second movable member relative to said rst movable member exceeds a predetermined value, said motion sensitive coupling means being a lluid coupling means including a piston connected to one of said movable members, and means dening a piston receiving cylinder connected to the other of said movable members.

2. The alarm system of claim 1, including:

means for pivotally supporting said rst movable member for movement in a generally vertical plane;

and means for pivotally supporting said second movable member for movement in a generally vertical plane.

3. The alarm system of claim 1, including:

an alarm;

an electrical power source;

an alarm control means including a solenoid and a solenoid actuated control switch having a fast operating time and a slow release time;

circuit means connecting said source, actuating switch, and solenoid in series and said source, alarm and alarm control switch in series;

a plunger actuated by said solenoid;

a movable arm pivotally connected for swinging movement toward and away from said plunger to operate said control switch;

means continuously urging said arm toward said plunger;

and viscous damping means connected to said movable arm to permit a slow return of said movable arm toward said plunger after operation of said control switch.

References Cited UNITED STATES PATENTS 1,006,898 l0/l9ll Beebee 340-244 1,942,700 1/1934 Henning 200-84 X 2,596,666 5/1952 Edgar et al. 200--84 3,001,184 9/1961 Edelman 340-261 JOHN W. CALDWELL, Primary Examiner D. L. TRAFTON, Assistant Examiner U.S. Cl. X.R. 200-84 

